Process for the preparation of 1,4-diaryl-2-fluoro-4-cyano-2-butenes and intermediates useful therefor

ABSTRACT

The present invention provides a process for the preparation of pesticidal 1,4-diaryl-2-fluoro-4-cyano-2 -butene compounds having the structural formula I  
                 
 
     and intermediates useful therefor

BACKGROUND OF THE INVENTION

[0001] Certain fluoroolefin compounds are known to possess insecticidaland acaricidal activity (see, e.g., U.S. Pat. No. 5,248,834; GB2,288,803-A; WO 94/06741; WO 97/16067; and U.S. Pat. No. 5,998,673.However, the fluoroolefin compounds disclosed in those patents andpatent applications are outside the scope of the present invention. U.S.Pat. No. 5,248,834 generically discloses certain1-aryl-1-(3-aryl-1,2-difluoroprop-1-enyl)cyclopropane compounds.However, that patent does not provide a method to prepare thosecompounds. In fact, U.S. Pat. No. 5,248,834 does not provide a method toprepare any fluoroolefin compounds.

[0002] 1,4-diaryl-2-fluoro-4-cyano-2-butenes and a method for theirpreparation are described in U.S. Pat. No. 5,998,673. Said compounds areuseful as insecticidal and acaricidal agents and for protecting plantsfrom damage caused by insect and acarid attack and infestation. Althougha method for the preparation of said agents is known, alternative moreeffective methods contribute to the enhanced availability of theseuseful insecticidal and acaricidal agents.

[0003] It is, therefore, an object of the present invention to provide aprocess for the preparation of 1,4-diaryl-2-fluoro-4-cyano-2-butenes.

[0004] It is also an object of the present invention to provideintermediates useful in said process.

[0005] These and other objects of the present invention will become moreapparent from the detailed description thereof set forth below.

SUMMARY OF THE INVENTION

[0006] The present invention provides a process for the preparation ofinsecticidal and acaricidal 1,4-diaryl-2-fluoro-4-cyano-2-butenecompounds of structural formula I

[0007] wherein

[0008] Ar is phenyl optionally substituted with any combination of fromone to three halogen, C₁-C₄alkyl, C₁-C₄haloalkyl, C₁-C₄alkoxy orC₁-C₄haloalkoxy groups,

[0009] 1- or 2-naphthyl optionally substituted with any combination offrom one to three halogen, C₁-C₄alkyl, C₁-C₄haloalkyl, C₁-C₄alkoxy orC₁-C₄haloalkoxy groups, or

[0010] a 5- or 6-membered heteroaromatic ring optionally substitutedwith any combination of from one to three halogen, C₁-C₄alkyl,C₁-C₄haloalkyl, C₁-C₄alkoxy or C₁-C₄haloalkoxy groups;

[0011] R is hydrogen, C₁-C₄alkyl, C₁-C₄haloalkyl, C₃-C₆cycloalkyl orC₃-C₆halocycloalkyl; and

[0012] Ar₁ is phenoxyphenyl optionally substituted with any combinationof from one to six halogen, C₁-C₄alkyl, C₁-C₄haloalkyl, C₁-C₄alkoxy orC₁-C₄haloalkoxy groups,

[0013] phenyl optionally substituted with any combination of from one tofive halogen, C₁-C₄alkyl, C₁-C₄haloalkyl, C₁-C₄alkoxy or C₁-C₄haloalkoxygroups,

[0014] biphenyl optionally substituted with any combination of from oneto five halogen, C₁-C₄alkyl, C₁-C₄haloalkyl, C₁-C₄alkoxy orC₁-C₄haloalkoxy groups,

[0015] phenoxypyridyl optionally substituted with any combination offrom one to five halogen, C₁-C₄alkyl, C₁-C₄haloalkyl, C₁-C₄alkoxy orC₁-C₄haloalkoxy groups,

[0016] benzylpyridyl optionally substituted with any combination of fromone to five halogen, C₁-C₄alkyl, C₁-C₄haloalkyl, C₁-C₄alkoxy orC₁-C₄haloalkoxy groups,

[0017] benzylphenyl optionally substituted with any combination of fromone to five halogen, C₁-C₄alkyl, C₁-C₄haloalkyl, C₁-C₄alkoxy orC₁-C₄haloalkoxy groups,

[0018] benzoylphenyl optionally substituted with any combination of fromone to five halogen, C₁-C₄alkyl, C₁-C₄haloalkyl, C₁-C₄alkoxy orC₁-C₄haloalkoxy groups,

[0019] 1- or 2-naphthyl optionally substituted with any combination offrom one to three halogen, C₁-C₄alkyl, C₁-C₄haloalkyl, C₁-C₄alkoxy orC₁-C₄haloalkoxy groups, or

[0020] a 5- or 6-membered heteroaromatic ring optionally substitutedwith any combination of from one to three halogen, C₁-C₄alkyl,C₁-C₄haloalkyl, C₁-C₄alkoxy or C₁-C₄haloalkoxy groups; or

[0021] the optical isomers thereof; or

[0022] the cis and trans isomers thereof

[0023] which process comprises the following steps:

[0024] (a) reacting an intermediate of formula II

[0025] wherein Ar₁ is defined as above and X is a nucleophilicreplaceabale leaving group, such as halogen, alkylsulphonyloxy orarylsulphonyloxy, especially chloro, bromo, iodo, tosyloxy, mesyloxy orthe like, with a cyanide delivering reagent in a first solvent to afforda cyano intermediate of formula III;

[0026] (b) reacting said cyano intermediate III with an aldehyde offormula IV

[0027] in the presence of a base in a second solvent to yield an anionwhich is acidified to afford a diene of formula V

[0028] and

[0029] (c) reacting said diene V with magnesium in the presence of athird solvent.

[0030] This invention also provides intermediate dienes of structuralformula V.

DETAILED DESCRIPTION OF THE INVENTION

[0031] Although a method for the preparation of insecticidal andacaricidal 1,4-diaryl-2-fluoro-4-cyano-2-butenes is described in U.S.Pat. No. 5,998,673, alternative more effective methods contribute to theenhanced availability of these useful insecticidal and acaricidalagents.

[0032] Advantageously, the present invention provides an effective andpractical method for the preparation of1,4-diaryl-2-fluoro-4-cyano-2-butenes of formula I,

[0033] wherein Ar, Ar₁ and R are defined as above.

[0034] In accordance with the process of the invention intermediate IIis treated with a cyanide delivering reagent in a polar aprotic solvent(first solvent) to afford the cyano intermediate III. Cyano intermediateIII is reacted with an aldehyde of formula IV in the presence of a baseoptionally in the presence of a second solvent to yield an intermediatewhich is acidified to afford a diene of formula V; and said diene V isreacted with magnesium in the presence of a protic solvent (thirdsolvent) to provide 1,4-diaryl-2-fluoro-4-cyano-2-butene I. The processis depicted in Flow Diagram I.

[0035] Intermediate aldehydes IV may be prepared as described in U.S.Pat. No. 5,998,673.

[0036] First solvents suitable for use in the inventive process includepolar aprotic solvents such as dimethylformamide, dimethylsulfoxide,N-methylpyrrolidone or the like, preferably dimethylsulfoxide.

[0037] Second solvents suitable for use in the inventive process includeaprotic solvents such as tetrahydrofuran, diethyl ether and the like,preferably tetrahydrofuran.

[0038] Third solvents suitable for use in the inventive process includeprotic solvents such as alkanols, preferably methanol or ethanol.

[0039] Cyanide ion delivering reagents include alkali metal cyanides andquarternary ammonium cyanides, preferably sodium cyanide or potassiumcyanide.

[0040] Bases suitable for use in the inventive process are alkali metalamides, such as lithium amide, lithium dimethylamide, lithiumdiisopropylamide, sodium bis(trimethylsilyl)amide,magnesiochlorodiethylamide (Et₂NMgCl), or the like, preferably lithiumdiisopropylamide.

[0041] Bases may be present in amounts ranging from catalytic to excessamounts such as 10 mole % to 4.0 molar excess.

[0042] Acids suitable for use in the process of the invention includestrong mineral acids such as HCl, HBr or H₂SO₄, preferably HCl or H₂SO₄.

[0043] In actual practice, intermediate II, preferably wherein X is Br,is treated with at least one molar equivalent of a cyanide deliveringreagent, preferably sodium cyanide, in a polar aprotic solvent,preferably dimethyl sulfoxide, to yield the cyano intermediate III; saidcyano intermediate III is treated with aldehyde IV in the presence of abase, preferable an alkali metal amide, preferably lithiumdiisopropylamide in an aprotic solvent, preferably tetrahydrofuran, toyield an intermediate which on acidification, preferably withhydrochloric acid, affords diene (V); said diene (V) is reacted withmagnesium in the presence of a protic solvent preferably an alkanol,preferably methanol, or ethanol, to provide the desired1,4-diaryl-2-fluoro-4-cyano-2-butene I.

[0044] The process depicted in Flow Diagram I provides1,4-diaryl-2-fluoro-4-cyano-2-butene I having predominantly the(Z)-configuration. Formula I compounds wherein the double bond is in the(E)—configuration may be prepared by isomerizing1,4-diaryl-2-fluoro-4-cyano-2-butene I which are predominantly in the(Z)—configuration using conventional procedures such as exposure tolight.

[0045] In formula I above, 5-and6-membered heteroaromatic rings include,but are not limited to, pyridyl, pyrazolyl, imidazolyl, triazolyl,isoxazolyl, tetrazolyl, pyrazinyl, pyridazinyl, triazinyl, furanyl,thienyl and thiazolyl rings each optionally substituted as described informula I above.

[0046] Exemplary of halogen hereinabove are fluorine, chlorine, bromineand iodine. The terms “C₁-C₄haloalkyl”, “C₃-C₆halocycloalkyl” and“C₁-C₄haloalkoxy” are defined as a C₁-C₄alkyl group, a C₃-C₆cycloalkylgroup and a C₁-C₄alkoxy group substituted with one or more halogenatoms, respectively.

[0047] The present invention also provides compounds of formula Vwherein the variables have the meanings as defined in formula I.

[0048] In compounds of formulae I and V respective following meaningsfor groups R are preferred: R is C₁-C₄alkyl; or C₃-C₆cycloalkylespecially isopropyl or cyclopropyl.

[0049] Compounds of formulae I and V, resp. are [referred. Wjereom Ardenotes phenyl which is substituted by halogen or C₁-C₄alkoxy.

[0050] Preference also is given to compounds of formulae I and V, resp.wherein Ar₁ is 3-phenoxyphenyl unsubstituted or substituted with anycombination of from one to six halogen, C₁-C₄alkyl, C₁-C₄haloalkyl,C₁-C₄alkoxy, or C₁-C₄haloalkoxy, 3-biphenyl unsubstituted or substitutedwith any combination of from one to five halogen, C₁-C₄alkyl,C₁-C₄haloalkyl, C1-C₄alkoxy or C₁-C₄haloalkoxy, or 3-benzylphenylsunsubstituted or substituted with any combination of from one to fivehalogen, C₁-C₄alkyl, C₁-C₄haloalkyl, C₁-C₄alkoxy or C₁-C₄haloalkoxy.

[0051] Moreover, particular preference is given to compounds wherein Ar₁is 3-phenoxyphenyl unsubstituted or substituted with any combination offrom one to six halogen, C₁-C₄alkyl, C₁-C₄haloalkyl, C₁-C₄alkoxy orC₁-C₄haloalkoxy, particularly 3-phenoxy-4-halogen-phenyl,3-(4′-halogen-phenoxy)-phenyl or3-(4′-halogen-phenoxy)-4-halogen-phenyl.

[0052] Compounds of formulae I and V, resp. are especially preferred

[0053] wherein

[0054] Ar is phenyl optionally substituted with any combination of fromone to three halogen, C₁-C₄alkyl, C₁-C₄haloalkyl, C1-C₄alkoxy orC₁-C₄haloalkoxy groups;

[0055] R is hydrogen, C₁-C₄alkyl, C₁-C₄haloalkyl, C₃-C₆cycloalkyl orC₃-C₆halocycloalkyl;

[0056] Ar₁ is 3-phenoxyphenyl optionally substituted with anycombination of from one to six halogen, C₁-C₄alkyl, C₁-C₄haloalkyl,C₁-C₄alkoxy or C₁-C₄haloalkoxy groups,

[0057] 3-biphenyl optionally substituted with any combination of fromone to five halogen, C₁-C₄alkyl, C₁-C₄haloalkyl, C₁-C₄alkoxy orC₁-C₄haloalkoxy groups, or

[0058] 3-benzylphenyl optionally substituted with any combination offrom one to five halogen, C₁-C₄alkyl, C₁-C₄haloalkyl, C₁-C₄alkoxy orC₁-C₄haloalkoxy groups.

[0059] Preferred compounds of the invention are those compounds offormula V wherein

[0060] Ar is phenyl optionally substituted with any combination of fromone to three halogen, C₁-C₄alkyl, C₁-C₄haloalkyl, C₁-C₄alkoxy orC₁-C₄haloalkoxy groups;

[0061] R is hydrogen, C₁-C₄alkyl, C₁-C₄haloalkyl, C₃-C₆cycloalkyl orC₃-C₆halocycloalkyl;

[0062] Ar₁ is 3-phenoxyphenyl optionally substituted with anycombination of from one to six halogen, C₁-C₄alkyl, C₁-C₄haloalkyl,C₁-C₄alkoxy or C₁-C₄haloalkoxy groups,

[0063] 3-biphenyl optionally substituted with any combination of fromone to five halogen, C₁-C₄alkyl, C₁-C₄haloalkyl, C₁-C₄alkoxy orC₁-C₄haloalkoxy groups, or

[0064] 3-benzylphenyl optionally substituted with any combination offrom one to five halogen, C₁-C₄alkyl, C₁-C₄haloalkyl, C₁-C₄alkoxy orC₁-C₄haloalkoxy groups.

[0065] More preferred compounds of the invention are those compounds offormula V wherein

[0066] Ar is phenyl optionally substituted with any combination of fromone to three halogen, C₁-C₄alkyl, C₁-C₄haloalkyl, C₁-C₄alkoxy orC₁-C₄haloalkoxy groups;

[0067] R is isopropyl or cyclopropyl; and

[0068] Ar₁ is 3-phenoxyphenyl optionally substituted with anycombination of from one to six halogen, C₁-C₄alkyl, C₁-C₄haloalkyl,C₁-C₄alkoxy or C₁-C₄haloalkoxy groups.

[0069] Particularly preferred compounds of the invention are thoseformula V compounds wherein

[0070] Ar is phenyl optionally substituted with any combination of fromone to three halogen, C₁-C₄alkyl, C₁-C₄haloalkyl, C₁-C₄alkoxy orC₁-C₄haloalkoxy groups;

[0071] R is cyclopropyl; and

[0072] Ar₁ is 3-phenoxyphenyl optionally substituted with anycombination of from one to six halogen, C₁-C₄alkyl, C₁-C₄haloalkyl,C₁-C₄alkoxy or C₁-C₄haloalkoxy groups.

[0073] Moreover, particular preference is given to compounds of formulaI′ and V′, resp. wherein the variables have the meanings given in tableA: TABLE A (I′)

(V′)

No. Z R Y W A-1 Cl cyclopropyl H H A-2 Cl CH(CH₃)₂ F H A-3 Cl CH(CH₃)₂ HH A-4 OCH₂CH₃ CH(CH₃)₂ F H A-5 OCH₂CH₃ CH(CH₃)₂ F H A-6 OCH₂CH₃cyclopropyl H H A-7 OCH₂CH₃ CH(CH₃)₂ H F A-8 Cl CH(CH₃)₂ H F A-9 Fcyclopropyl F H A-10 OCH₂CH₃ cyclopropyl H H A-11 F cyclopropyl H H

[0074] With due modification of the starting compounds, the protocolsshown in the synthesis examples below were used for obtaining furthercompounds I and V.

EXAMPLE 1

[0075]

[0076] A mixture of α-bromo-4-fluoro-3-phenoxytoluene (2.65 g, 0.0094mol) and sodium cyanide (0.735 g, 0.0141 mol) in dimethyl sulfoxide (15ml) was heated at 50° C. for 35 min and 90° C. for 35 min. The cooledreaction mixture was diluted with water and extracted with ethylacetate. The combined organic extracts were washed with water, saturatedbrine, dried over anhydrous sodium sulfate, and concentrated in vacuo toan off-white oil (1.8 g, 85.7%) which is characterized by IR, ¹HNMR,¹³CNMR and ¹⁹FNMR analyses.

EXAMPLE 2

[0077]

[0078] To a stirred solution of (4-fluoro-3-phenoxyphenyl) -acetonitrile(447.2 mg, 2.1 mmol) in anhydrous tetrahydrofuran (5 ml) under nitrogenat −78° C. is added via syringe a solution of lithium diisopropylamidein tetrahydrofuran (1.16 ml of 0.20M, 2.31 mmol). The reaction mixtureis allowed to warm to room temperature and then stirred for 2 hr. Thestirred reaction mixture is then cooled to −-78° C. and a solution ofp-chloro-β-cyclopropyl-α-fluorocinnamaldehyde (449.3 mg, 2 mmol) intetrahydrofuran (2 ml) is added via syringe. The reaction mixture isallowed to warm to room temperature and stirred for 48 hr. The reactionmixture is diluted with ethyl acetate and 2N hydrochloric acid, and thelayers separated. The aqueous layer is extracted with ethyl acetate, andthe combined organic layers washed with 2N hydrochloric acid, water,dried over anhydrous sodium sulfate and concentrated in vacuo to a brownresidue. Flash chromatography of this residue on silica gel eluting withethyl acetate/hexane ({fraction (1/9)}) afforded the title compound as asyrup (500 mg, 55.3%), which solidified on trituration with ether toyield a pale yellow solid (mp 110-112° C.) which is characterized by¹HNMR, ¹³CNMR, ¹⁹FNMR, IR and mass spectral analyses.

EXAMPLE 3

[0079]

[0080] A mixture of 1-(p-chlorophenyl)-1-cyclopropyl-2-fluoro-4-(4-fluoro-3-phenoxyphenyl)-4-cyano-1,3-butadiene (335 mg, 0.77 mmol)and magnesium (93.8 mg, 3.86 mmol) in methanol (3 ml) and anhydrous THF(2 ml) is refluxed under nitrogen for 3 hr. The cooled reaction mixtureis acidified with 2N hydrochloric and extracted with ethyl acetate. Thecombined extracts are washed with 2N hydrochloric acid, water, driedover anhydrous sodium sulfate, and concentrated in vacuo. The residue ischromatographed on silica gel eluting with ethyl acetate/hexane({fraction (5/95)}) to afford the title compound as a colorless oil (46mg, 14%) which is characterized by ¹HNMR, ¹³CNMR, ¹⁹FNMR, IR and massspectral analyses.

What is claimed is:
 1. A process for the preparation of a compound offormula I

wherein Ar is phenyl optionally substituted with any combination of fromone to three halogen, C₁-C₄alkyl, C₁-C₄haloalkyl, C₁-C₄alkoxy orC₁-C₄haloalkoxy groups, or 1- or 2-naphthyl optionally substituted withany combination of from one to three halogen, C₁-C₄alkyl,C₁-C₄haloalkyl, C₁-C₄alkoxy or C₁-C₄haloalkoxy groups; R is hydrogen,C₁-C₄alkyl, C₁-C₄haloalkyl, C₃-C₆cycloalkyl or C₃-C₆halocycloalkyl; andAr₁ is phenoxyphenyl optionally substituted with any combination of fromone to six halogen, C₁-C₄alkyl, C₁-C₄haloalkyl, C₁-C₄alkoxy orC₁-C₄haloalkoxy groups, phenyl optionally substituted with anycombination of from one to five halogen, C₁-C₄alkyl, C₁-C₄haloalkyl,C₁-C₄alkoxy or C₁-C₄haloalkoxy groups, biphenyl optionally substitutedwith any combination of from one to five halogen, C₁-C₄alkyl,C₁-C₄haloalkyl, C₁-C₄alkoxy or C₁-C₄haloalkoxy groups, phenoxypyridyloptionally substituted with any combination of from one to five halogen,C₁-C₄alkyl, C₁-C₄haloalkyl, C₁-C₄alkoxy or C₁-C₄haloalkoxy groups,benzylpyridyl optionally substituted with any combination of from one tofive halogen, C₁-C₄alkyl, C₁-C₄haloalkyl, C₁-C₄alkoxy or C₁-C₄haloalkoxygroups, benzylphenyl optionally substituted with any combination of fromone to five halogen, C₁-C₄alkyl, C₁-C₄haloalkyl, C₁-C₄alkoxy orC₁-C₄haloalkoxy groups, benzoylphenyl optionally substituted with anycombination of from one to five halogen, C₁-C₄alkyl, C₁-C₄haloalkyl,C₁-C₄alkoxy or C₁-C₄haloalkoxy groups, 1- or 2-naphthyl optionallysubstituted with any combination of from one to three halogen,C₁-C₄alkyl, C₁-C₄haloalkyl, C₁-C₄alkoxy or C₁-C₄haloalkoxy groups; orthe optical isomers thereof; or the cis and trans isomers thereof, whichprocess comprises the following steps: a) reacting an intermediate offormula II

wherein Ar₁ is defined as above and X is chloro, bromo, iodo, tosyloxy,mesyloxy or the like with a cyanide delivering reagent in a firstsolvent to afford a cyano intermediate of formula III

b) reacting said cyano intermediate III with an aldehyde of formula IV

in the presence of a base in a second solvent to yield an anion which isacidified to afford a diene of formula V

c) reacting said diene of formula V with magnesium in the presence of athird solvent to give the desired formula I product.
 2. The processaccording to claim 1 wherein said cyanide delivering reagent is analkali metal cyanide.
 3. The process according to claim 2 wherein thealkali metal cyanide is sodium cyanide or potassium cyanide.
 4. Theprocess according to claim 1 wherein said first solvent is a polaraprotic solvent selected from the group consisting of dimethylsulfoxide,dimethylformamide and N-methylpyrrolidone.
 5. The process according toclaim 4 wherein the polar aprotic solvent is dimethylsulfoxide.
 6. Theprocess according to claim 1 wherein the said base is an alkali metalamide.
 7. The process according to claim 6 wherein the alkali metalamide is lithium diisopropylamide.
 8. The process according to claim 1wherein said acid is a strong mineral acid.
 9. The process according toclaim 8 wherein said strong mineral acid is sulfuric acid orhydrochloric acid.
 10. The process according to claim 1 wherein saidthird solvent is an alkanol.
 11. The process according to claim 10wherein the alkanol is methanol or ethanol.
 12. A compound of formula Ior V

wherein Ar is phenyl optionally substituted with any combination of fromone to three halogen, C₁-C₄alkyl, C₁-C₄haloalkyl, C₁-C₄alkoxy orC₁-C₄haloalkoxy groups, 1- or 2-naphthyl optionally substituted with anycombination of from one to three halogen, C₁-C₄alkyl, C₁-C₄haloalkyl,C₁-C₄alkoxy or C₁-C₄haloalkoxy groups, or R is hydrogen, C₁-C₄alkyl,C₁-C₄haloalkyl, C₃-C₆cycloalkyl or C₃-C₆halocycloalkyl; Ar₁ isphenoxyphenyl optionally substituted with any combination of from one tosix halogen, C₁-C₄alkyl, C₁-C₄haloalkyl, C₁-C₄alkoxy or C₁- C₄haloalkoxygroups, phenyl optionally substituted with any combination of from oneto five halogen, C₁-C₄alkyl, C₁-C₄haloalkyl, C₁-C₄alkoxy orC₁-C₄haloalkoxy groups, biphenyl optionally substituted with anycombination of from one to five halogen, C₁-C₄alkyl, C₁-C₄haloalkyl,C₁-C₄alkoxy or C₁-C₄haloalkoxy groups, phenoxypyridyl optionallysubstituted with any combination of from one to five halogen,C₁-C₄alkyl, C₁-C₄haloalkyl, C₁-C₄alkoxy or C₁-C₄haloalkoxy groups,benzylpyridyl optionally substituted with any combination of from one tofive halogen, C₁-C₄alkyl, C₁-C₄haloalkyl, C₁-C₄alkoxy or C₁-C₄haloalkoxygroups, benzylphenyl optionally substituted with any combination of fromone to five halogen, C₁-C₄alkyl, C₁-C₄haloalkyl, C₁-C₄alkoxy orC₁-C₄haloalkoxy groups, benzoylphenyl optionally substituted with anycombination of from one to five halogen, C₁-C₄alkyl, C₁-C₄haloalkyl,C₁-C₄alkoxy or C₁-C₄haloalkoxy groups, 1- or 2-naphthyl optionallysubstituted with any combination of from one to three halogen,C₁-C₄alkyl, C₁-C₄haloalkyl, C₁-C₄alkoxy or C₁-C₄haloalkoxy groups; orthe optical isomers thereof; or the cis and trans isomers thereof. 13.The compound of formula V according to claim 12 wherein Ar is phenyloptionally substituted with any combination of from one to threehalogen, C₁-C₄alkyl, C₁-C₄haloalkyl, C₁-C₄alkoxy or C₁- C₄haloalkoxygroups; R and is hydrogen, C₁-C₄alkyl, C₁-C₄haloalkyl, C₃-C₆cycloalkylor C₃-C₆halocycloalkyl; Ar₁is 3-phenoxyphenyl optionally substitutedwith any combination of from one to six halogen, C₁-C₄alkyl,C₁-C₄haloalkyl, C₁-C₄alkoxy or C₁-C₄haloalkoxy groups, 3-biphenyloptionally substituted with any combination of from one to five halogen,C₁-C₄alkyl, C₁-C₄haloalkyl, C₁-C₄alkoxy or C₁-C₄haloalkoxy groups, or3-benzylphenyl optionally substituted with any combination of from oneto five halogen, C₁-C₄alkyl, C₁-C₄haloalkyl, C₁-C₄alkoxy orC₁-C₄haloalkoxy groups.
 14. The compound according to claim 13 whereinAr is phenyl optionally substituted with any combination of from one tothree halogen, C₁-C₄alkyl, C₁-C₄haloalkyl, C₁-C₄alkoxy orC₁-C₄haloalkoxy groups; R is isopropyl or cyclopropyl; and Ar₁ is3-phenoxyphenyl optionally substituted with any combination of from oneto six halogen, C₁-C₄alkyl, C₁-C₄haloalkyl, C₁-C₄alkoxy orC₁-C₄haloalkoxy groups.
 15. The compound according to claim 14 whereinAr is phenyl optionally substituted with any combination of from one tothree halogen, C₁-C₄alkyl, C₁-C₄haloalkyl, C₁-C₄alkoxy orC₁-C₄haloalkoxy groups; R is cyclopropyl; and Ar₁ is 3-phenoxyphenyloptionally substituted with any combination of from one to six halogen,C₁-C₄alkyl, C₁-C₄haloalkyl, C₁-C₄alkoxy or C₁-C₄haloalkoxy groups.